Thermal Management System And An Electric Vehicle Including The Thermal Management System

ABSTRACT

A thermal management system (1) for controlling the temperature in a cabin (2) and an energy storage system (3) of an electric vehicle including a vehicle component (4). Also, an electric vehicle comprising the thermal management system (1). The system (1) comprises one heat exchanger (5) and one heater (6) arranged to heat the cabin (2) and to provide heat to the heat exchanger (5). The system (1) comprises a first valve (7) for thermal fluid, a first temperature sensor (8) and a control unit (9) arranged to determine (S4) if the cabin (2) or the energy storage system (3) is to be heated, based on a received temperature of the first temperature sensor (8), the temperature in the cabin (2) and in the energy storage system (3), to determine (S5) if there is excess heat in the thermal fluid, and to control (S6) the opening and closing of the first valve (7) so that the thermal fluid is provided to the heater (6) when there is excess heat in the thermal fluid and any of the energy storage system (3) and the cabin (2) is to be heated.

TECHNICAL FIELD

The present disclosure relates to a thermal management system forcontrolling the temperature in a cabin and an energy storage system ofan electric vehicle including a vehicle component. The presentdisclosure also relates to an electric vehicle comprising the thermalmanagement system.

BACKGROUND

Electric vehicles are becoming more and more popular. On the one handside they are preferable for environmental reasons, by avoiding fossilfuels, and on the other hand side they are, most of the cases, preferredin regard to reduced total cost of ownership.

Cars are not the only type of vehicle that can be an electric vehicle.For example, boats, trucks, locomotives, airplanes and heavy-dutyvehicles are also available as electrical vehicles.

Electric vehicles are usually powered by an energy storage system duringoperation. The energy storage system here being defined as any kind ofbattery, battery pack or series of batteries for powering the electricvehicle.

For the usability of electric vehicles, it is important that the energystorage system has a long lifetime, i.e. a large number ofcharge/discharge cycles possible before the cells fail to operatesatisfactorily. Keeping the energy storage system in an optimaltemperature range is essential to maximize the lifetime.

Besides improving the energy storage system lifetime, keeping the energystorage system within the optimal temperature range during operationensures that the energy storage system deliver as much power aspossible.

As well as keeping the energy storage system at an optimal temperature,the temperature in the cabin, where the operator and passengers of thevehicle are housed, should also be regulated.

There are many systems for managing temperatures in the energy storagesystem and the cabin. For example in U.S. Pat. No. 7,789,176 B2, athermal management system is presented which has a cooling loop forcooling the drive motor, a refrigeration subsystem which providescooling to a heat exchanger, an energy storage cooling subsystem with acoolant cooled via heat transfer in the heat exchanger, and a HVACsubsystem that provides temperature control for the vehicle's passengercabin. The HVAC subsystem is also coupled to the heat exchanger for itscoolant to be cooled by the refrigeration subsystem and to the coolingloop for cooling the drive motor for its coolant to be heated by thecooling loop. In this solution, heat in the cooling loop for the drivemotor can be used for heating the cabin and cold from the refrigerationsubsystem can be used to cool both the energy storage system and thecabin. The energy storage cooling subsystem also has a heater if theenergy storage system needs heating.

In an electric vehicle, the power for heating and cooling comes from theenergy storage system. Therefore, it is essential that the thermalmanagement is as energy efficient as possible so that more of the powerof the energy storage system can be used for operating the electricvehicle.

Another important aspect of thermal management in an electric vehicle isthat it takes up space in the vehicle as well as increases the weight. Aspace efficient and weight optimized thermal management system istherefore preferable.

SUMMARY

It is an aim of the present disclosure to at least partly overcome theabove problems, and to provide an improved thermal management system forcontrolling the temperature in a cabin and an energy storage system ofan electric vehicle including a vehicle component.

This aim is achieved by a device as defined in claim 1.

The disclosure provides a thermal management system for controlling thetemperature in a cabin and an energy storage system of an electricvehicle including a vehicle component. The system comprises one heatexchanger arranged to heat the energy storage system, one heaterarranged to heat the cabin when the cabin temperature is colder than auser selected temperature and to provide heat to the heat exchanger whenthe energy storage system is colder than a minimum temperature, a firstvalve arranged to receive thermal fluid that has been used for coolingthe vehicle component, the first valve having an openable and closableoutlet in fluid communication with the heater, a first temperaturesensor arranged to measure the temperature of the received thermalfluid, and a control unit. The control unit is arranged to:

-   -   receive the measured temperature of the thermal fluid from the        first temperature sensor,    -   receive data associated with a measured temperature in the        cabin,    -   receive data associated with a measured temperature in the        energy storage system,    -   determine if any of the cabin or the energy storage system is to        be heated, based on the received data,    -   determine if there is excess heat in the thermal fluid based on        the received measured temperature of the thermal fluid, and    -   control the opening and closing of the outlet of the first valve        so that the thermal fluid is provided to the heater via the        outlet of the first valve when there is excess heat in the        thermal fluid and any of the energy storage system and the cabin        is to be heated.

The vehicle component can be any component of the electric vehicle thatrequires cooling with a thermal fluid. For example, the vehiclecomponent can be one or more parts of the power train, any kind ofe-motor, inverter or DC/DC converter.

The thermal management system is arranged so that excess heat fromcooling the vehicle component can be used to heat the cabin and theenergy storage system. For example, the excess heat can be used to heatboth the cabin and the energy storage system. For the cabin, the heat isprovided to a cooling and heating unit, e.g. a heating, ventilation, andair conditioning, HVAC unit, arranged in the cabin.

Using the data from the temperature sensor and input data associatedwith a measured temperature in the cabin and the energy storage system,the control unit can control the first valve so that excess heat fromthe vehicle component can be used in the cabin, the energy storagesystem or in both. Thus, the use of energy from the energy storagesystem for heating the cabin and the energy storage system is reduced.Accordingly, the energy in the energy storage system will last longer,and the energy storage system needs to be charged less frequently.

The same heater is used to heat both the cabin and the energy storagesystem. By minimizing the number of heaters, the weight of the system isminimized. Furthermore, during operation of the electric vehicle, it isthe energy storage system that powers any heaters. Therefore, it is alsoan advantage that only one heater is used for all heating in the thermalmanagement system. Cost is also reduced by having only one heater.

With the term “to determine if there is excess heat in the thermalfluid” is meant to determine if the thermal fluid is warm enough tocontribute to the heating of the cabin and the energy storage system.

According to some aspects, the heater comprises a heater temperaturesensor arranged to measure the temperature of the thermal fluid in theheater, and the control unit is arranged to receive the measuredtemperature of the thermal fluid in the heater from the heatertemperature sensor and to determine if there is excess heat in thethermal fluid based on the received measured temperature of the thermalfluid from the first temperature sensor and the measured temperature ofthe thermal fluid in the heater.

According to some aspects, the control unit is arranged to determinethat there is excess heat in the thermal fluid if the measuredtemperature of the thermal fluid from the first temperature sensor iswarmer than the measured temperature of the thermal fluid in the heater.Thus, an efficient way of determining if there is excess heat in thethermal fluid that has been used for cooling the vehicle component, isachieved. If the measured temperature of the thermal fluid from thefirst temperature sensor is warmer than the measured temperature of thethermal fluid in the heater, the thermal fluid from cooling the vehiclecomponent will be useful for heating the cabin and/or the energy storagesystem.

In other words, if the thermal fluid from cooling the vehicle componentis warmer than the thermal fluid entering the heater, the thermal fluidfrom cooling the vehicle component would heat the thermal fluid enteringthe heater and accordingly there is excess heat in the thermal fluidfrom cooling the vehicle component.

According to some aspects, the thermal management system comprises onecooling unit arranged to cool the cabin when the cabin is warmer than auser selected temperature and to provide cold to the heat exchanger forcooling the energy storage system when the energy storage system iswarmer than a predetermined maximum temperature. The same cooling unitis thus used for cooling both the cabin and the energy storage system.By minimizing the number of heaters and cooling units, the weight of theunit is minimized. Since, during operation of the electric vehicle, itis the energy storage system that powers the heater and the coolingunit, it is also an advantage that only one heater and only one coolingunit is used for all heating and cooling. Cost is also reduced by havingonly one cooling unit.

According to some aspects, the thermal management system comprises asecond valve, which is a three-way valve, arranged with an inlet fromthe heater, a first outlet to the cabin and a second outlet to the heatexchanger, and the control unit is arranged to control the flow ofthermal fluid through the second valve. The control unit thus controlsthe flow to the cabin and the energy storage system via the secondvalve. In other words, the control unit controls the second valve tocontrol if the thermal fluid is to flow to the cabin, to the energystorage system or to both.

According to some aspects, the control unit is arranged to:

-   -   control the opening and closing of the first outlet of the        second valve so that the thermal fluid is provided to the cabin        when there is excess heat in the thermal fluid and the cabin is        to be heated,    -   control the opening and closing of the second outlet of the        second valve so that the thermal fluid is provided to the heat        exchanger when there is excess heat in the thermal fluid and the        energy storage system is to be heated.

According to some aspects, the thermal management system comprises athird valve, which is a three-way valve, arranged with an inlet from theenergy storage system, a first outlet to the heat exchanger and a secondoutlet to an external passive cooling system, and wherein the controlunit is arranged to:

-   -   control the opening and closing of the first outlet and second        outlet of the third valve so that a third thermal fluid which is        used to heat or cool the energy storage system is directed        either to the heat exchanger or to the external passive cooling        system.

In a case when there is no need to heat or cool the energy storagesystem, the control unit may control the third valve so that the thermalfluid does not pass the heat exchanger. The valve can also be controlledso that the fluid only passes the heat exchanger.

According to some aspects, the thermal management system comprises asecond temperature sensor, arranged to measure the temperature of thethermal fluid entering the third valve. The control unit is arranged to:

-   -   receive the measured temperature of the third thermal fluid from        the second temperature sensor,    -   control the opening and closing of the first outlet and the        second outlet of the third valve based on the received        temperature.

With the measured temperature, together with the data associated with ameasured temperature in the energy storage system, it is known if theenergy storage system needs heating or cooling. The control unit maythus control the third valve based on the received data. It should benoted that the second temperature sensor may be external to the thermalmanagement system.

According to some aspects, the first valve has a second openable andclosable outlet and the thermal management system comprises a fourthvalve. The control unit is arranged to:

-   -   control the opening and closing of the fourth valve so that it        is opened when the first outlet of the first valve is opened and        closed when the first outlet of the first valve is closed, and    -   control the opening and closing of the second outlet so that it        is opened when the first outlet of the first valve is closed and        opened when the first outlet of the first valve is closed.

With this, it is possible to have a loop for the thermal fluid forcooling the vehicle component when there is no excess heat in thethermal fluid or if the cabin or energy storage system does not need anyheat.

According to some aspects, the thermal management system comprises oneor more pumps and wherein the control unit is arranged to:

-   -   control the speed of the one or more pumps based on the based on        the received the received data and on the received measured        temperature.

Thus, besides controlling one or more valves, the control unit may alsocontrol the flow of thermal fluid through one or more pumps. The controlunit can thus have more control over the system and also use flow rateas a factor when heating or cooling.

According to some aspects, the heat exchanger is a chiller. A chiller isa plate-to-plate heat exchanger that transfers thermal energy from athermal fluid to another thermal fluid, or from one fluid to severalfluids.

The aim is also achieved by an electric vehicle as defined in claim 12.The vehicle comprises a cabin, an energy storage system, a vehiclecomponent, a thermal fluid for cooling the vehicle component, and thethermal management system according to the invention. The vehicle is,for example, of a short-distance type, such as bulldozers andexcavators, which are carrying out work within a small area and notintended for long distance travels. The vehicle can also be of along-distance type, such as cars, busses and trucks, intended fortransportation of people and/or goods.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained more closely by the description ofdifferent aspects and with reference to the appended figures.

FIG. 1 shows a schematic diagram of an example thermal managementsystem.

FIG. 2 shows a schematic diagram of an example thermal management systemwith added input of a temperature sensor.

FIG. 3 shows a schematic diagram of an example thermal management systemwith added control of an additional valve.

FIG. 4 shows a schematic diagram of an example thermal management systemwith added control of an additional valve.

FIG. 5 shows a schematic diagram of an example thermal management systemwith added input of an additional temperature sensor.

FIG. 6 shows a schematic diagram of an example thermal management systemwith added control of an additional valve.

FIG. 7 shows a schematic diagram of an example thermal management systemwith added control of one or more pumps.

FIG. 8 shows a schematic diagram of an example thermal management systemwith examples of added temperature sensors, pumps, pressure sensors anda thermal expansion valve.

DETAILED DESCRIPTION

The present invention is not limited to the embodiments disclosed butmay be varied and modified within the scope of the following claims. Forexample, pumps, temperature sensors and pressure sensors may be added tomany different places in the thermal management system. Some examples ofwhere it may be advantageous to add pumps, temperature sensors and/orpressure sensors are described below.

Aspects of the present disclosure will be described more fullyhereinafter with reference to the accompanying drawings. The thermalmanagement system disclosed herein can, however, be realized in manydifferent forms and should not be construed as being limited to theaspects set forth herein. Like numbers in the drawings refer to likeelements throughout.

The terminology used herein is for the purpose of describing particularaspects of the disclosure only and is not intended to limit thedisclosure. As used herein, the singular forms “a”, “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. Unless otherwise defined, all terms (includingtechnical and scientific terms) used herein have the same meaning ascommonly understood by one of ordinary skill in the art to which thisdisclosure belongs.

As also stated in the background section, an energy storage system isherein being defined as any kind of battery pack or series of batteriesfor powering the electric motor of the electric vehicle. In other words,when the term energy storage system is used in this disclosure, asingular battery or a plurality of batteries is included in the term. Anenergy storage system for an electric vehicle usually comprises severalbatteries in series.

FIG. 1 shows a schematic diagram of an example thermal management system1. The thermal management system 1 is for controlling the temperature ina cabin 2 and an energy storage system 3 of an electric vehicleincluding a vehicle component 4. Dotted lines in FIG. 1 represents partsthat are not included in the thermal management system 1. Continuouslines represent included parts. The same applies to aspects describedbelow with the associated figures.

The vehicle component is any component of the electric vehicle thatrequires cooling with a thermal fluid. For example, the vehiclecomponent can be any kind of e-motor, inverter or

DC/DC converter.

The thermal management system 1 comprises one heat exchanger 5 arrangedto heat the energy storage system 3, one heater 6 arranged to heat thecabin 2 when the cabin temperature is colder than a user selectedtemperature, and to provide heat to the heat exchanger 5 when the energystorage system 3 is colder than a minimum temperature. The heatexchanger 5 is arranged to transfer thermal energy from a thermal fluidto another thermal fluid, or from one fluid to several fluids. The heatexchanger 5 is, for example, a chiller. A chiller is a plate-to-plateheat exchanger that transfers thermal energy from a thermal fluid toanother thermal fluid, or from one fluid to several fluids. The heater 6is for example a high voltage heater, a Low-Voltage resistor heater, aPTC-type heater, or an AC-powered heater. It could also be thecondensing part of a heat-pump system. The heater 6 may be any heaterfor heating thermal fluids suitable to be arranged in an electricvehicle. It should be noted that the same heater 6 is used to both heatthe cabin 2 and to heat the energy storage system 3. The heater ispowered by the energy storage system 3 but it may also be powered by anexternal power source when the electric vehicle is connected to such,for example when it is charging.

The system 1 comprises a first valve 7 having an inlet 7 a arranged toreceive a thermal fluid from the vehicle component 4, which thermalfluid has been used for cooling the vehicle component 4. The first valve7 has an openable and closable first outlet 7 b in fluid communicationwith the heater 6. In other words, the first valve 7 receives thermalfluid that has been used to cool the vehicle component 4 of the electricvehicle. The thermal fluid passes on to the heater 6 if the first outlet7 b is open. The thermal fluid is transported in a passage 14 a, thepassage being for example piping. In the figures, the passages 14 a-care illustrated as lines, and arrows in connection with the lines showthe flow direction of the thermal fluid. The first valve 7 can be anykind of valve with an inlet and an openable and closable outlet. Thevalve is a valve that can be controlled via signals from a control unit,either via wire or wireless signals. The same applies to any valvesdescribed below.

A first temperature sensor 8 is arranged to measure the temperature ofthe received thermal fluid that has been used for cooling the vehiclecomponent 4. The first temperature sensor 8 is, for example, arranged inthe first valve 7 or in a passage before the thermal fluid enters thefirst valve 7.

The thermal management system 1 comprises a control unit 9. The controlunit 9 is arranged to:

-   -   receive S1 the measured temperature of the thermal fluid from        the first temperature sensor 8,    -   receive S2 data associated with a measured temperature in the        cabin 2,    -   receive S3 data associated with a measured temperature in the        energy storage system 3,    -   determine S4 if any of the cabin 2 or the energy storage system        3 are to be heated, based on the received data,    -   determine S5 if there is excess heat in the thermal fluid based        on the received measured temperature of the thermal fluid, and    -   control S6 the opening and closing of the first outlet 7 b of        the first valve 7 so that the thermal fluid is provided to the        heater 6 via the first outlet 7 b of the first valve 7 when        there is excess heat in the thermal fluid and any of the energy        storage system 3 and the cabin 2 is to be heated.

The thermal management system 1 is arranged so that excess heat fromcooling the vehicle component 4 can be used for heating and cooling inthe cabin 2 and in an energy storage system 3. The same heater 6 in theunit is used to heat both the cabin 2 and the energy storage system 3.Using the data from the temperature sensor and input data associatedwith a measured temperature in the cabin 2 and the energy storage system3, the control unit 9 can control the first valve 7 so that excess heatfrom the vehicle component 4 can be used in the cabin 2, the energystorage system 3 or in both.

By minimizing the number of heaters, the weight of the system isminimized. Furthermore, during operation of the electric vehicle, it isthe energy storage system 3 that powers any heaters. Therefore, it isalso an advantage that only one heater 6 is used for all heating in thethermal management system 1. Cost is also reduced by having only oneheater 6.

The steps S1 to S6 are illustrated in FIG. 1. The control unit 9comprises processing circuitry for processing data and either comprisescommunication circuitry or is connected to communication circuitry forreceiving sensor data and sending instructions for the components it iscontrolling. Communication between the control unit 9 and thecomponents, i.e. any valves, pumps, pressure sensors and/or thermalexpansion valves, may comprise wired or wireless communication.

The data associated with a measured temperature in the cabin 2 may bedata indicating an actual temperature in the cabin 2 or a number ofdegrees that the cabin 2 is differing from a desired temperature. Forexample, if the cabin 2 is set to be 22° C. to be comfortable to anoperator of the electric vehicle, and the actual temperature is 20° C.,the data associated with a measured temperature in the cabin 2 may be20° C. In such a case the control unit 9 compares the desiredtemperature to the measured temperature to determine that more heat isneeded. It may also be that the data associated with a measuredtemperature in the cabin 2 is −2° C. to indicate that the cabin 2 needstwo more degrees to reach the desired temperature. It may also be thatthe data associated with a measured temperature only gives an indicationthat more heat is needed, without a specific number. It may also be thatthe data associated with a measured temperature is given in percentwhere, for example, 0% is an indication that no heating or cooling isrequired, and each percent represents a predetermined number of degreesto be changed.

The data associated with a measured temperature in the energy storagesystem 3 may be in a corresponding form. Either an actual temperature issent to the control unit 9, and in the case of large battery packs, theactual temperature may be an average of several temperature sensorsarranged in different locations in the energy storage system 3, or thedifference between the actual temperature is sent, or only an indicationof whether the energy storage system 3 needs to be heated is sent.

The data associated with a measured temperature in the cabin 2 and theenergy storage system 3 may also be indicated in other ways thandescribed above.

To determine S4 if any of the cabin 2 or the energy storage system 3 isto be heated, based on the received data, may be different depending onin which way the received data indicates the measured temperature asdiscussed above. If an actual temperature of the cabin 2 or energystorage system 3 is received, determining S4 if any of the cabin 2 orthe energy storage system 3 is to be heated may comprise comparing thereceived data to a reference list or to a previously received desiredtemperature of the cabin 2. If it is a difference in desired temperatureand actual temperature, the determining may be to determine if the cabin2 or energy storage system 3 is too warm or too cold. If the dataassociated with a measured temperature only gives an indication thatmore heat is needed, then the determining may only be to check thereceived data.

To control S6 the opening and closing of the first outlet 7 b of thefirst valve 7 so that the thermal fluid is provided to the heater 6 viathe first outlet 7 b of the first valve 7 when there is excess heat inthe thermal fluid and any of the energy storage system 3 and the cabin 2is to be heated may comprise to send a signal to the valve withinstructions to open the first outlet 7 b. This is done when the thermalfluid from the vehicle component 4 is so warm that it can be used toheat the cabin 2 or the energy storage system 3.

The control unit 9 may also be arranged to communicate with the electricvehicle and receive instructions, give feedback to the electric vehicle,as well as receive and transmit states of the electric vehicle and thethermal management system and potential errors in the thermal managementsystem 1 or the used components.

It should be noted that there are parts illustrated in the FIGS. 1-7that are not part of the thermal management system 1. For example, thevehicle component 4, and its cooling system with thermal fluid, areparts of the vehicle. Also, a passive cooling system 25, is oftenpresent in electric vehicles but are not part of the described thermalmanagement system 1. The cabin 2 and the heating and cooling system,e.g. HVAC, of the cabin 2 are parts of the vehicle and not included inthe thermal management system 1. A cooling unit 10 is optional in thesystem and is described below. Valves 11, 12 and 13 are also optionalfor the system.

In FIG. 1, an example of how the thermal management system 1 can beconnected to parts in the vehicle is illustrated. Three passages 14 a-cfor cooling is passing a passive cooling system 25 of the vehicle. Theinner passage 14 a is used to cool the vehicle component 4 of theelectric vehicle. The thermal management system 1 comprises atemperature sensor 8 to determine if there is excess heat in the thermalfluid. This means to determine if the thermal fluid used for cooling theexternal component is warm enough to contribute to the heating of thecabin and the energy storage system. If not, the thermal fluid can becircled back to the passive cooling system 25 via a second outlet 7 c ofthe first valve 7. If there is excessive heat, the thermal fluid can bepassed on to the heater 6, via the first outlet 7 b of the valve 7 sothat the heater can heat the thermal fluid less than without the heatfrom the thermal fluid from the vehicle component. In this example, thethermal management system 1 comprises a second valve 11 which can beused to determine if the thermal fluid then should be used to heat thecabin or the energy storage system via the heat exchanger or both.

The middle passage 14 b via the passive cooling system 25 goes via acooling unit 10 and a second thermal fluid in this passage 14 b is usedto cool the cabin and/or the energy storage system via the heatexchanger 5.

The thermal management system may comprise a third valve 12. The outerpassage 14 c is used for cooling the energy storage system and isselectively connected to the heat exchanger 5 via the third valve 12.The third thermal fluid of the outer passage 14 c can be both heated andcooled at the heat exchanger. When it is to be cooled, it is cooled viathe heat exchanger by the second thermal fluid and when it is heated, itis heated via the heat exchanger by the thermal fluid from the heater 6.

The heater 6 may comprise a heater temperature sensor 6 a arranged tomeasure the temperature of the thermal fluid in the heater 6, asillustrated in FIG. 2. In that case, to determine S5 if there is excessheat in the thermal fluid based on the received measured temperature ofthe thermal fluid comprises to receive S5 a the measured temperature ofthe thermal fluid in the heater 6 from the heater temperature sensor,and to determine S5 b if the measured temperature of the thermal fluidfrom the first temperature sensor 8 is warmer than the measuredtemperature of the thermal fluid in the heater 6. Thus, an efficient wayof determining if there is excess heat in the thermal fluid that hasbeen used for cooling the vehicle component, is achieved. If themeasured temperature of the thermal fluid from the first temperaturesensor is warmer than the measured temperature of the thermal fluid inthe heater, the thermal fluid from cooling the vehicle component will beuseful for heating the cabin and/or the energy storage system. In otherwords, if the thermal fluid from cooling the vehicle component is warmerthan the thermal fluid entering the heater, the thermal fluid fromcooling the vehicle component would heat the thermal fluid entering theheater and accordingly there is excess heat in the thermal fluid fromcooling the vehicle component. The heater temperature sensor 6 a mayalso be arranged outside of the heater 6 as a separate component.

An alternative way to determine S5, if there is excess heat in thethermal fluid used for cooling the vehicle component 4 based on thereceived measured temperature of the thermal fluid, is to compare thereceived measured temperature in the thermal fluid used for cooling thevehicle component 4 to a temperature of the thermal fluid measured at afourth temperature sensor 18, which is described further below inassociation with FIG. 8.

The thermal management system 1 may comprise one cooling unit 10arranged to cool the cabin 2 when the cabin 2 is warmer than a userselected temperature and to provide cold to the heat exchanger 5 forcooling the energy storage system 3 when the energy storage system 3 iswarmer than a predetermined maximum temperature. The same cooling unit10 is thus used for cooling both the cabin 2 and the energy storagesystem 3. By minimizing the number of heaters and cooling units, theweight of the unit is minimized. Since, during operation of the electricvehicle, it is the energy storage system 3 that powers the heater 6 andthe cooling unit 10, it is also an advantage that only one heater 6, andonly one cooling unit 10 is used for all heating and cooling. The costof the system is also minimized by having only one heater 6 and onecooling unit 10.

The cooling unit 10 is for example a compressor which, together with athermal expansion valve arranged in association with an evaporator inthe cabin and the heat exchanger, forms two refrigeration machines. Insuch a case, the middle passage 14 b that is connected to the compressor10 is for transporting a second thermal fluid in the form of a thermalvapor. The cooling unit 10 may also be a heat-pump system.

The control unit 9 may also be arranged to control the power to theheater 6 and thus how much the thermal fluid flowing through the heater6 should be heated. The control may be based on the same parameters asthe control of the first valve 7, i.e. the temperature of the thermalfluid and the data associated with the temperature of the cabin 2 and/orenergy storage system 3.

FIG. 3 shows a schematic diagram of an example thermal management system1 with added control of an additional valve. The thermal managementsystem 1 may comprise a second valve 11, which is a three-way valve,arranged with an inlet 11 a from the heater 6, a first outlet 11 b tothe cabin 2 and a second outlet 11 c to the heat exchanger 5, and thecontrol unit 9 is arranged to control the flow of thermal fluid throughthe second valve 11. The control unit 9 thus controls the flow to thecabin 2 and the energy storage system 3 via the second valve 11. Inother words, the control unit 9 controls the second valve and thus ifthe thermal fluid is to flow from the heater 6 to the cabin 2, to theenergy storage system 3 or to both.

To control the second valve 11, the control unit 9 may be arranged tocontrol S7 the opening and closing of the first outlet 11 b of thesecond valve 11 so that the thermal fluid is provided to the cabin 2when there is excess heat in the thermal fluid, and the cabin 2 is to beheated, and to control S8 the opening and closing of the second outlet11 c of the second valve 11 so that the thermal fluid is provided to theheat exchanger 5 when there is excess heat in the thermal fluid and theenergy storage system 3 is to be heated.

FIG. 4 shows a schematic diagram of an example thermal management system1 with added control of an additional valve. The thermal managementsystem 1 may comprise a third valve 12, which is a three-way valve,arranged with an inlet 12 a from the energy storage system 3, a firstoutlet 12 b to the heat exchanger 5 and a second outlet 12 c to apassive cooling system 25 of the vehicle, and wherein the control unit 9is arranged to control S9 the opening and closing of the first outlet 12b and second outlet 12 c of the third valve 12 so that a second thermalfluid which is used to heat or cool the energy storage system 3 isdirected either to the heat exchanger 5 or to the passive cooling system25. In a case when there is no need to heat or cool the energy storagesystem 3, the control unit 9 may control the third valve so that thethermal fluid does not pass the heat exchanger 5, i.e. close the firstoutlet 12 b. The valve can also be controlled so that the fluid onlypasses the heat exchanger 5, i.e. open the first outlet 12 b and closethe second outlet 12 c.

FIG. 5 shows a schematic diagram of an example thermal management system1 with added input of an additional temperature sensor. The thermalmanagement system 1 may comprise a second temperature sensor 20,arranged to measure the temperature of the thermal fluid entering thethird valve 12. The control unit 9 is then arranged to receive S9 a themeasured temperature of the thermal fluid from the second temperaturesensor 20 and to control S9 b the opening and closing of the firstoutlet 12 b and the second outlet 12 c of the third valve 12 based onthe received temperature.

With the measured temperature, together with the data associated with ameasured temperature in the energy storage system 3, it is known if theenergy storage system 3 needs heating or cooling. The control unit 9 maythus control the third valve 12 based on the received data. It should benoted that the second temperature sensor 20 may be a part of the vehiclecomprising the thermal management system 1.

FIG. 6 shows a schematic diagram of an example thermal management system1 with added control of an additional valve. The first valve 7 has asecond openable and closable outlet 7 c. The thermal management system 1comprises a fourth valve 13. The control unit 9 is then arranged tocontrol S10 the opening and closing of the fourth valve 13 so that it isopened when the first outlet 7 b of the first valve 7 is opened, andclosed when the first outlet 7 b of the first valve 7 is closed, and tocontrol S11 the opening and closing of the second outlet 7 c so that itis opened when the first outlet 7 b of the first valve 7 is closed andopened when the first outlet 7 b of the first valve 7 is closed.

With this, it is possible to have a loop for the thermal fluid forcooling the vehicle component 4 when there is no excess heat in thethermal fluid or if the cabin 2 or energy storage system 3 does not needany heat. As can be seen in FIG. 6, if the first valve 7 and the fourthvalve 13 are both closed, a loop where the vehicle component 4 is cooledvia the passive cooling system 25 is created. When both valves 7, 13 areopen, the thermal fluid from cooling the vehicle component 4 is used toheat the cabin 2 or the energy storage system 3 or both.

FIG. 7 shows a schematic diagram of an example thermal management system1 with added control of one or more pumps 15, 16, 17. The thermalmanagement system 1 may comprise one or more pumps 15, 16, 17 and thecontrol unit 9 is then arranged to control S12 the speed of the one ormore pumps 15, 16, 17 based on the based on the received data and thereceived measured temperature. Thus, besides controlling one or morevalves, the control unit 9 may also control the flow of thermal fluidthrough one or more pumps 15, 16, 17. The control unit 9 can thus havemore control over the system and also use flow rate as a factor whenheating or cooling. The first pump 15, the second pump 16 and the thirdpump 17 may be added to the system independently from each other.

The controlling of all valves and pumps may also be based on theselected temperature and the predetermined minimum temperature of theenergy storage system 3.

FIG. 8 shows a schematic diagram of an example thermal management system1 with examples of added temperature sensors 18, 19, 20, 21, pumps 15,16, 17, pressure sensors 22, 23 and a thermal expansion valve 24. Onlythe parts described in claim 1 are necessary to achieve the aim of thedisclosure. Other parts are optional or arranged outside of the systemas has also been explained above.

The pressure sensors 22, 23 are indicative of the temperature if thepassages 14 are transporting refrigerant gas. The pressure sensors 22,23 may be arranged in the vehicle comprising the system 1. The controlunit can use input from the pressure sensor to, for example, control thethermal expansion valve 24 and/or the cooling unit 10. When the thermalfluid is a refrigerant gas, it is for example R134a or R1234YF orsimilar. It should be noted that different parts of the piping may holddifferent types of thermal fluid, such as a glycol coolant, water or arefrigerant gas. In general, passages that transport thermal fluid forcooling has a refrigerant gas and passages for heating comprises athermal liquid. But other solutions are possible.

The thermal expansion valve 24 controls the amount of refrigerantreleased into the evaporator, which is a part of the heat exchanger andis intended to regulate the superheat of the vapor leaving theevaporator. The thermal expansion valve may also be integrated in theheat exchanger, or a thermal expansion valve may be arranged in thevehicle comprising the system 1. The thermal expansion valve can bepressure controlled or electrical controlled.

It can be electrically engaged (normally closed or normally opened) orjust pressure engaged.

LIST OF REFERENCES

-   1. Thermal management system-   2. Cabin-   3. Energy storage system-   4. Vehicle component-   5. Heat exchanger-   6. Heater

a. Heater temperature sensor

-   7. First valve

a. Inlet

b. First outlet

c. Second outlet

-   8. First temperature sensor-   9. Control unit-   10. Cooling unit-   11. Second valve

a. Inlet

b. First outlet

c. Second outlet

-   12. Third valve

a. Inlet

b. First outlet

c. Second outlet

-   13. Fourth valve-   14. Passage for thermal fluid

a. First passage

b. Second passage

c. Third passage

-   15. First pump-   16. Second pump-   17. Third pump-   18. Fourth temperature sensor-   19. Third temperature sensor-   20. Second temperature sensor-   21. Fifth temperature sensor-   22. First pressure sensor-   23. Second pressure sensor-   24. Thermal expansion valve-   25. External passive cooling system

1. A thermal management system for controlling the temperature in acabin and an energy storage system of an electric vehicle including avehicle component, the system comprising: one heat exchanger arranged toheat the energy storage system, one heater arranged to heat the cabinwhen the cabin temperature is colder than a user selected temperatureand to provide heat to the heat exchanger when the energy storage systemis colder than a minimum temperature, a first valve arranged to receivea thermal fluid that has been used for cooling the vehicle component,the first valve having an openable and closable outlet in fluidcommunication with the heater, a first temperature sensor arranged tomeasure the temperature of the received thermal fluid, and a controlunit arranged to: receive the measured temperature of the thermal fluidfrom the first temperature sensor, receive data associated with ameasured temperature in the cabin, receive data associated with ameasured temperature in the energy storage system, determine if any ofthe cabin or the energy storage system is to be heated, based on thereceived data, determine if there is excess heat in the thermal fluidbased on the received measured temperature of the thermal fluid used forcooling the vehicle component, and control the opening and closing ofthe outlet of the first valve so that the thermal fluid is provided tothe heater via the outlet of the first valve when there is excess heatin the thermal fluid and any of the energy storage system and the cabinis to be heated.
 2. The thermal management system according to claim 1,wherein the heater comprises a heater temperature sensor arranged tomeasure the temperature of the thermal fluid in the heater, and thecontrol unit is arranged to receive the measured temperature of thethermal fluid in the heater from the heater temperature sensor and todetermine if there is excess heat in the thermal fluid based on thereceived measured temperature of the thermal fluid from the firsttemperature sensor and the measured temperature of the thermal fluid inthe heater.
 3. The thermal management system according to claim 1,comprising: one cooling unit arranged to cool the cabin when the cabinis warmer than a user selected temperature and to provide cold to theheat exchanger for cooling the energy storage system when the energystorage system is warmer than a predetermined maximum temperature. 4.The thermal management system according to claim 1, comprising a secondvalve, which is a three-way valve, arranged with an inlet arranged toreceive the thermal fluid from the heater, a first outlet in fluidcommunication with the cabin and a second outlet in fluid communicationwith the heat exchanger, and the control unit is arranged to control theflow of thermal fluid through the second valve.
 5. The thermalmanagement system according to claim 4, wherein the control unit isarranged to: control the opening and closing of the first outlet of thesecond valve so that the thermal fluid is provided to the cabin whenthere is excess heat in the thermal fluid and the cabin is to be heated,control the opening and closing of the second outlet of the second valveso that the thermal fluid is provided to the heat exchanger when thereis excess heat in the thermal fluid and the energy storage system is tobe heated.
 6. The thermal management system according to claim 1,comprising a third valve, which is a three-way valve, arranged with aninlet from the energy storage system, a first outlet to the heatexchanger and a second outlet to an external passive cooling system, andwherein the control unit (is arranged to: control the opening andclosing of the first outlet and second outlet of the third valve so thata third thermal fluid which is used to heat or cool the energy storagesystem is directed either to the heat exchanger or to the externalpassive cooling system.
 7. The thermal management system according toclaim 6, comprising a second temperature sensor, arranged to measure thetemperature of the third thermal fluid entering the third valve, andwherein the control unit is arranged to: receive the measuredtemperature of the third thermal fluid from the second temperaturesensor, control the opening and closing of the first outlet and thesecond outlet of the third valve based on the received temperature. 8.The thermal management system according to claim 1, wherein the firstvalve has a second openable and closeable outlet and the thermalmanagement system comprises a fourth valve wherein the control unit isarranged to: control the opening and closing of the fourth valve so thatit is opened when the first outlet of the first valve is opened andclosed when the first outlet of the first valve is closed, and controlthe opening and closing of the second outlet so that it is opened whenthe first outlet of the first valve is closed and opened when the firstoutlet of the first valve is closed.
 9. The thermal management systemaccording to claim 1, comprising one or more pumps and wherein thecontrol unit is arranged to: control the speed of the one or more pumpsbased on the based on the received the received data and on the receivedmeasured temperature.
 10. The thermal management system according toclaim 1, wherein the heat exchanger is a chiller.
 11. An electricvehicle comprising a cabin, an energy storage system, a vehiclecomponent, a thermal fluid for cooling the vehicle component, and athermal management system including: one heat exchanger arranged to heatthe energy storage system one heater arranged to heat the cabin when thecabin temperature is colder than a user selected temperature and toprovide heat to the heat exchanger when the energy storage system iscolder than a minimum temperature, a first valve arranged to receive athermal fluid that has been used for cooling the vehicle component, thefirst valve having an openable and closable outlet in fluidcommunication with the heater, a first temperature sensor arranged tomeasure the temperature of the received thermal fluid, and a controlunit arranged to: receive the measured temperature of the thermal fluidfrom the first temperature sensor, receive data associated with ameasured temperature in the cabin, receive data associated with ameasured temperature in the energy storage system, determine if any ofthe cabin or the energy storage system is to be heated, based on thereceived data, determine if there is excess heat in the thermal fluidbased on the received measured temperature of the thermal fluid used forcooling the vehicle component, and control the opening and closing ofthe outlet of the first valve so that the thermal fluid is provided tothe heater via the outlet of the first valve when there is excess heatin the thermal fluid and any of the energy storage system and the cabinis to be heated.
 12. The electric vehicle according to claim 11, whereinthe thermal management system further comprises a heater temperaturesensor arranged to measure the temperature of the thermal fluid in theheater, and the control unit is arranged to receive the measuredtemperature of the thermal fluid in the heater from the heatertemperature sensor and to determine if there is excess heat in thethermal fluid based on the received measured temperature of the thermalfluid from the first temperature sensor and the measured temperature ofthe thermal fluid in the heater.
 13. The electric vehicle according toclaim 11, wherein the thermal management system further comprises onecooling unit arranged to cool the cabin when the cabin is warmer than auser selected temperature and to provide cold to the heat exchanger forcooling the energy storage system when the energy storage system iswarmer than a predetermined maximum temperature.
 14. The electricvehicle according to claim 11, wherein the thermal management systemfurther comprises a second valve, which is a three-way valve, arrangedwith an inlet arranged to receive the thermal fluid from the heater, afirst outlet in fluid communication with the cabin and a second outletin fluid communication with the heat exchanger, and the control unit isarranged to control the flow of thermal fluid through the second valve.15. The electric vehicle according to claim 11, wherein the control unitis arranged to: control the opening and closing of the first outlet ofthe second valve so that the thermal fluid is provided to the cabin whenthere is excess heat in the thermal fluid and the cabin is to be heated,control the opening and closing of the second outlet of the second valveso that the thermal fluid is provided to the heat exchanger when thereis excess heat in the thermal fluid and the energy storage system is tobe heated.